30 mph to ft/s — 30 miles per hour in feet per second
Exact 30 × 1.466667 = 44
30 miles per hour in other units
| Metres per second | 13.4112 | m/s |
|---|---|---|
| Kilometres per hour | 48.28032 | km/h |
| Feet per second | 44 | ft/s |
| Knots | 26.069287 | kn |
mph to ft/s at a glance
| Miles per hour | Feet per second |
|---|---|
| 1 mph | 1.466667 ft/s |
| 2 mph | 2.933333 ft/s |
| 3 mph | 4.4 ft/s |
| 5 mph | 7.333333 ft/s |
| 10 mph | 14.666667 ft/s |
| 20 mph | 29.333333 ft/s |
| 25 mph | 36.666667 ft/s |
| 50 mph | 73.333333 ft/s |
| 100 mph | 146.666667 ft/s |
| 250 mph | 366.666667 ft/s |
| 500 mph | 733.333333 ft/s |
| 1,000 mph | 1,466.67 ft/s |
How to convert miles per hour to feet per second
Multiply by 1.466667 — one mile per hour is 1.466667 feet per second. That factor is exact: it comes from the definition of the units rather than from a measurement, so it will not change and does not need rounding.
Working 30 × 1.466667 = 44
In words: forty-four feet per second.
Questions
How many feet per second are in a mile per hour?
One mile per hour is 1.466667 feet per second. This figure is exact — it comes from the definition of the unit, not a measurement.
What is 30 miles per hour in feet per second?
30 miles per hour is 44 feet per second. The working is 30 × 1.466667 = 44.
What is a knot?
One nautical mile per hour — and a nautical mile is one minute of latitude, fixed at exactly 1,852 metres. That is the whole point of it: a ship making 10 knots for six hours has covered one degree of latitude, which you can read straight off a chart without converting anything.
Why do sailors and pilots say "knots" and not "knots per hour"?
Because the "per hour" is already inside the word. A knot is a speed, not a distance, so "knots per hour" would be an acceleration. The name comes from the knotted rope once paid out behind a ship and counted against a sand glass.
What's the quick way to convert mph to km/h in my head?
Multiply by 1.6, or add 60%. For the other direction, take away a third and then a little more. Fifty mph is 80 km/h, 60 is 97, 70 is 113 — worth remembering if you drive across a border where the signs change.
Why isn't Mach on this page?
Because it is not a fixed unit. Mach 1 is the local speed of sound, which falls as air gets colder — around 1,235 km/h at sea level but closer to 1,062 km/h in the stratosphere where airliners cruise. A single conversion factor would be wrong nearly everywhere.